BJ_web_developers / webportal

  [HTML5 Boilerplate homepage](https://html5boilerplate.com) | [Documentation
  table of contents](TOC.md)
  
  # Extend and customise HTML5 Boilerplate
  
  Here is some useful advice for how you can make your project with HTML5
  Boilerplate even better. We don't want to include it all by default, as
  not everything fits with everyone's needs.
  
  
  * [App Stores](#app-stores)
  * [DNS prefetching](#dns-prefetching)
  * [Google Universal Analytics](#google-universal-analytics)
  * [Internet Explorer](#internet-explorer)
  * [Miscellaneous](#miscellaneous)
  * [News Feeds](#news-feeds)
  * [Search](#search)
  * [Social Networks](#social-networks)
  * [URLs](#urls)
  * [Web Apps](#web-apps)
  
  
  ## App Stores
  
  ### Install a Chrome Web Store app
  
  Users can install a Chrome app directly from your website, as long as
  the app and site have been associated via Google's Webmaster Tools.
  Read more on [Chrome Web Store's Inline Installation
  docs](https://developer.chrome.com/webstore/inline_installation).
  
  ```html
  <link rel="chrome-webstore-item" href="https://chrome.google.com/webstore/detail/APP_ID">
  ```
  
  ### Smart App Banners in iOS 6+ Safari
  
  Stop bothering everyone with gross modals advertising your entry in the
  App Store. Include the following [meta tag](https://developer.apple.com/library/IOS/documentation/AppleApplications/Reference/SafariWebContent/PromotingAppswithAppBanners/PromotingAppswithAppBanners.html#//apple_ref/doc/uid/TP40002051-CH6-SW2)
  will unintrusively allow the user the option to download your iOS app,
  or open it with some data about the user's current state on the website.
  
  ```html
  <meta name="apple-itunes-app" content="app-id=APP_ID,app-argument=SOME_TEXT">
  ```
  
  ## DNS prefetching
  
  In short, DNS Prefetching is a method of informing the browser of domain names
  referenced on a site so that the client can resolve the DNS for those hosts,
  cache them, and when it comes time to use them, have a faster turn around on
  the request.
  
  ### Implicit prefetches
  
  There is a lot of prefetching done for you automatically by the browser. When
  the browser encounters an anchor in your html that does not share the same
  domain name as the current location the browser requests, from the client OS,
  the IP address for this new domain. The client first checks its cache and
  then, lacking a cached copy, makes a request from a DNS server. These requests
  happen in the background and are not meant to block the rendering of the
  page.
  
  The goal of this is that when the foreign IP address is finally needed it will
  already be in the client cache and will not block the loading of the foreign
  content. Fewer requests result in faster page load times. The perception of this
  is increased on a mobile platform where DNS latency can be greater.
  
  #### Disable implicit prefetching
  
  ```html
  <meta http-equiv="x-dns-prefetch-control" content="off">
  ```
  
  Even with X-DNS-Prefetch-Control meta tag (or http header) browsers will still
  prefetch any explicit dns-prefetch links.
  
  **_WARNING:_** THIS MAY MAKE YOUR SITE SLOWER IF YOU RELY ON RESOURCES FROM
  FOREIGN DOMAINS.
  
  ### Explicit prefetches
  
  Typically the browser only scans the HTML for foreign domains. If you have
  resources that are outside of your HTML (a javascript request to a remote
  server or a CDN that hosts content that may not be present on every page of
  your site, for example) then you can queue up a domain name to be prefetched.
  
  ```html
  <link rel="dns-prefetch" href="//example.com">
  <link rel="dns-prefetch" href="https://ajax.googleapis.com">
  ```
  
  You can use as many of these as you need, but it's best if they are all
  immediately after the [Meta
  Charset](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/meta#attr-charset)
  element (which should go right at the top of the `head`), so the browser can
  act on them ASAP.
  
  #### Common Prefetch Links
  
  Amazon S3:
  
  ```html
  <link rel="dns-prefetch" href="//s3.amazonaws.com">
  ```
  
  Google APIs:
  
  ```html
  <link rel="dns-prefetch" href="https://ajax.googleapis.com">
  ```
  
  Microsoft Ajax Content Delivery Network:
  
  ```html
  <link rel="dns-prefetch" href="//ajax.microsoft.com">
  <link rel="dns-prefetch" href="//ajax.aspnetcdn.com">
  ```
  
  ### Further reading about DNS prefetching
  
  * https://developer.mozilla.org/en-US/docs/Controlling_DNS_prefetching
  * https://dev.chromium.org/developers/design-documents/dns-prefetching
  * http://blogs.msdn.com/b/ie/archive/2011/03/17/internet-explorer-9-network-performance-improvements.aspx
  * http://dayofjs.com/videos/22158462/web-browsers_alex-russel
  
  
  ## Google Universal Analytics
  
  ### More tracking settings
  
  The [optimized Google Universal Analytics
  snippet](https://mathiasbynens.be/notes/async-analytics-snippet#universal-analytics)
  included with HTML5 Boilerplate includes something like this:
  
  ```js
  ga('create', 'UA-XXXXX-X', 'auto'); ga('send', 'pageview');
  ```
  
  To customize further, see Google's [Advanced
  Setup](https://developers.google.com/analytics/devguides/collection/analyticsjs/advanced),
  [Pageview](https://developers.google.com/analytics/devguides/collection/analyticsjs/pages),
  and [Event](https://developers.google.com/analytics/devguides/collection/analyticsjs/events) Docs.
  
  ### Anonymize IP addresses
  
  In some countries, no personal data may be transferred outside jurisdictions
  that do not have similarly strict laws (i.e. from Germany to outside the EU).
  Thus a webmaster using the Google Universal Analytics may have to ensure that
  no personal (trackable) data is transferred to the US. You can do that with
  [the `ga('set', 'anonymizeIp', true);`
  parameter](https://developers.google.com/analytics/devguides/collection/analyticsjs/advanced#anonymizeip)
  before sending any events/pageviews. In use it looks like this:
  
  ```js
  ga('create', 'UA-XXXXX-X', 'auto');
  ga('set', 'anonymizeIp', true);
  ga('send', 'pageview');
  ```
  
  ### Track jQuery AJAX requests in Google Analytics
  
  An article by @JangoSteve explains how to [track jQuery AJAX requests in Google
  Analytics](http://www.alfajango.com/blog/track-jquery-ajax-requests-in-google-analytics/).
  
  Add this to `plugins.js`:
  
  ```js
  /*
   * Log all jQuery AJAX requests to Google Analytics
   * See: http://www.alfajango.com/blog/track-jquery-ajax-requests-in-google-analytics/
   */
  if (typeof ga !== "undefined" && ga !== null) {
      $(document).ajaxSend(function(event, xhr, settings){
          ga('send', 'pageview', settings.url);
      });
  }
  ```
  
  ### Track JavaScript errors in Google Analytics
  
  Add this function after `ga` is defined:
  
  ```js
  (function(window){
      var undefined,
          link = function (href) {
              var a = window.document.createElement('a');
              a.href = href;
              return a;
          };
      window.onerror = function (message, file, line, column) {
          var host = link(file).hostname;
          ga('send', {
            'hitType': 'event',
            'eventCategory': (host == window.location.hostname || host == undefined || host == '' ? '' : 'external ') + 'error',
            'eventAction': message,
            'eventLabel': (file + ' LINE: ' + line + (column ? ' COLUMN: ' + column : '')).trim(),
            'nonInteraction': 1
          });
      };
  }(window));
  ```
  
  ### Track page scroll
  
  Add this function after `ga` is defined:
  
  ```js
  $(function(){
      var isDuplicateScrollEvent,
          scrollTimeStart = new Date,
          $window = $(window),
          $document = $(document),
          scrollPercent;
  
      $window.scroll(function() {
          scrollPercent = Math.round(100 * ($window.height() + $window.scrollTop())/$document.height());
          if (scrollPercent > 90 && !isDuplicateScrollEvent) { //page scrolled to 90%
              isDuplicateScrollEvent = 1;
              ga('send', 'event', 'scroll',
                  'Window: ' + $window.height() + 'px; Document: ' + $document.height() + 'px; Time: ' + Math.round((new Date - scrollTimeStart )/1000,1) + 's'
              );
          }
      });
  });
  ```
  
  ## Internet Explorer
  
  ### Prompt users to switch to "Desktop Mode" in IE10 Metro
  
  IE10 does not support plugins, such as Flash, in Metro mode. If
  your site requires plugins, you can let users know that via the
  `x-ua-compatible` meta element, which will prompt them to switch
  to Desktop Mode.
  
  ```html
  <meta http-equiv="x-ua-compatible" content="requiresActiveX=true">
  ```
  
  Here's what it looks like alongside H5BP's default `x-ua-compatible`
  values:
  
  ```html
  <meta http-equiv="x-ua-compatible" content="ie=edge,requiresActiveX=true">
  ```
  
  You can find more information in [Microsoft's IEBlog post about prompting for
  plugin use in IE10 Metro
  Mode](http://blogs.msdn.com/b/ie/archive/2012/01/31/web-sites-and-a-plug-in-free-web.aspx).
  
  ### IE Pinned Sites (IE9+)
  
  Enabling your application for pinning will allow IE9 users to add it to their
  Windows Taskbar and Start Menu. This comes with a range of new tools that you
  can easily configure with the elements below. See more [documentation on IE9
  Pinned Sites](https://msdn.microsoft.com/en-us/library/gg131029.aspx).
  
  ### Name the Pinned Site for Windows
  
  Without this rule, Windows will use the page title as the name for your
  application.
  
  ```html
  <meta name="application-name" content="Sample Title">
  ```
  
  ### Give your Pinned Site a tooltip
  
  You know — a tooltip. A little textbox that appears when the user holds their
  mouse over your Pinned Site's icon.
  
  ```html
  <meta name="msapplication-tooltip" content="A description of what this site does.">
  ```
  
  ### Set a default page for your Pinned Site
  
  If the site should go to a specific URL when it is pinned (such as the
  homepage), enter it here. One idea is to send it to a special URL so you can
  track the number of pinned users, like so:
  `http://www.example.com/index.html?pinned=true`
  
  ```html
  <meta name="msapplication-starturl" content="http://www.example.com/index.html?pinned=true">
  ```
  
  ### Recolor IE's controls manually for a Pinned Site
  
  IE9+ will automatically use the overall color of your Pinned Site's favicon to
  shade its browser buttons. UNLESS you give it another color here. Only use
  named colors (`red`) or hex colors (`#ff0000`).
  
  ```html
  <meta name="msapplication-navbutton-color" content="#ff0000">
  ```
  
  ### Manually set the window size of a Pinned Site
  
  If the site should open at a certain window size once pinned, you can specify
  the dimensions here. It only supports static pixel dimensions. 800x600
  minimum.
  
  ```html
  <meta name="msapplication-window" content="width=800;height=600">
  ```
  
  ### Jump List "Tasks" for Pinned Sites
  
  Add Jump List Tasks that will appear when the Pinned Site's icon gets a
  right-click. Each Task goes to the specified URL, and gets its own mini icon
  (essentially a favicon, a 16x16 .ICO). You can add as many of these as you
  need.
  
  ```html
  <meta name="msapplication-task" content="name=Task 1;action-uri=http://host/Page1.html;icon-uri=http://host/icon1.ico">
  <meta name="msapplication-task" content="name=Task 2;action-uri=http://microsoft.com/Page2.html;icon-uri=http://host/icon2.ico">
  ```
  
  ### (Windows 8) High quality visuals for Pinned Sites
  
  Windows 8 adds the ability for you to provide a PNG tile image and specify the
  tile's background color. [Full details on the IE
  blog](http://blogs.msdn.com/b/ie/archive/2012/06/08/high-quality-visuals-for-pinned-sites-in-windows-8.aspx).
  
  * Create a 144x144 image of your site icon, filling all of the canvas, and
    using a transparent background.
  * Save this image as a 32-bit PNG and optimize it without reducing
    colour-depth. It can be named whatever you want (e.g. `metro-tile.png`).
  * To reference the tile and its color, add the HTML `meta` elements described
    in the IE Blog post.
  
  ### (Windows 8) Badges for Pinned Sites
  
  IE10 will poll an XML document for badge information to display on your app's
  tile in the Start screen. The user will be able to receive these badge updates
  even when your app isn't actively running. The badge's value can be a number,
  or one of a predefined list of glyphs.
  
  * [Tutorial on IEBlog with link to badge XML schema](http://blogs.msdn.com/b/ie/archive/2012/04/03/pinned-sites-in-windows-8.aspx)
  * [Available badge values](https://msdn.microsoft.com/en-us/library/ie/br212849.aspx)
  
  ```html
  <meta name="msapplication-badge" value="frequency=NUMBER_IN_MINUTES;polling-uri=http://www.example.com/path/to/file.xml">
  ```
  
  ### Disable link highlighting upon tap in IE10
  
  Similar to [-webkit-tap-highlight-color](http://davidwalsh.name/mobile-highlight-color)
  in iOS Safari. Unlike that CSS property, this is an HTML meta element, and its
  value is boolean rather than a color. It's all or nothing.
  
  ```html
  <meta name="msapplication-tap-highlight" content="no" />
  ```
  
  You can read about this useful element and more techniques in
  [Microsoft's documentation on adapting WebKit-oriented apps for IE10](https://blogs.windows.com/buildingapps/2012/11/15/adapting-your-webkit-optimized-site-for-internet-explorer-10/)
  
  ## Search
  
  ### Direct search spiders to your sitemap
  
  [Learn how to make a sitemap](http://www.sitemaps.org/protocol.html)
  
  ```html
  <link rel="sitemap" type="application/xml" title="Sitemap" href="/sitemap.xml">
  ```
  
  ### Hide pages from search engines
  
  According to Heather Champ, former community manager at Flickr, you should not
  allow search engines to index your "Contact Us" or "Complaints" page if you
  value your sanity. This is an HTML-centric way of achieving that.
  
  ```html
  <meta name="robots" content="noindex">
  ```
  
  **_WARNING:_** DO NOT INCLUDE ON PAGES THAT SHOULD APPEAR IN SEARCH ENGINES.
  
  ### Firefox and IE Search Plugins
  
  Sites with in-site search functionality should be strongly considered for a
  browser search plugin. A "search plugin" is an XML file which defines how your
  plugin behaves in the browser. [How to make a browser search
  plugin](https://www.google.com/search?ie=UTF-8&q=how+to+make+browser+search+plugin).
  
  ```html
  <link rel="search" title="" type="application/opensearchdescription+xml" href="">
  ```
  
  
  ## Miscellaneous
  
  * Use [polyfills](https://github.com/Modernizr/Modernizr/wiki/HTML5-Cross-browser-Polyfills).
  
  * Use [Microformats](http://microformats.org/wiki/Main_Page) (via
    [microdata](http://microformats.org/wiki/microdata)) for optimum search
    results
    [visibility](http://googlewebmastercentral.blogspot.com/2009/05/introducing-rich-snippets.html).
  
  * If you're building a web app you may want [native style momentum scrolling in
    iOS 5+](http://www.johanbrook.com/articles/native-style-momentum-scrolling-to-arrive-in-ios-5/)
    using `-webkit-overflow-scrolling: touch`.
  
  * If you want to disable the translation prompt in Chrome or block Google
    Translate from translating your web page, use [`<meta name="google"
    value="notranslate">`](https://support.google.com/translate/?hl=en#2641276).
    To disable translation for a particular section of the web page, add
    [`class="notranslate"`](https://support.google.com/translate/?hl=en#2641276).
  
  * If you want to disable the automatic detection and formatting of possible
    phone numbers in Safari on iOS, use [`<meta name="format-detection"
    content="telephone=no">`](https://developer.apple.com/library/safari/documentation/AppleApplications/Reference/SafariHTMLRef/Articles/MetaTags.html/#//apple_ref/doc/uid/TP40008193-SW5).
  
  * Avoid development/stage websites "leaking" into SERPs (search engine results
    page) by [implementing X-Robots-tag
    headers](https://github.com/h5bp/html5-boilerplate/issues/804).
  
  * Screen readers currently have less-than-stellar support for HTML5 but the JS
    script [accessifyhtml5.js](https://github.com/yatil/accessifyhtml5.js) can
    help increase accessibility by adding ARIA roles to HTML5 elements.
  
  
  ## News Feeds
  
  ### RSS
  
  Have an RSS feed? Link to it here. Want to [learn how to write an RSS feed from
  scratch](http://www.rssboard.org/rss-specification)?
  
  ```html
  <link rel="alternate" type="application/rss+xml" title="RSS" href="/rss.xml">
  ```
  
  ### Atom
  
  Atom is similar to RSS, and you might prefer to use it instead of or in
  addition to it. [See what Atom's all
  about](http://www.atomenabled.org/developers/syndication/).
  
  ```html
  <link rel="alternate" type="application/atom+xml" title="Atom" href="/atom.xml">
  ```
  
  ### Pingbacks
  
  Your server may be notified when another site links to yours. The href
  attribute should contain the location of your pingback service.
  
  ```html
  <link rel="pingback" href="">
  ```
  
  * High-level explanation: https://codex.wordpress.org/Introduction_to_Blogging#Pingbacks
  * Step-by-step example case: http://www.hixie.ch/specs/pingback/pingback-1.0#TOC5
  * PHP pingback service: https://web.archive.org/web/20131211032834/http://blog.perplexedlabs.com/2009/07/15/xmlrpc-pingbacks-using-php/
  
  
  
  ## Social Networks
  
  ### Facebook Open Graph data
  
  You can control the information that Facebook and others display when users
  share your site. Below are just the most basic data points you might need. For
  specific content types (including "website"), see [Facebook's built-in Open
  Graph content
  templates](https://developers.facebook.com/docs/opengraph/objects/builtin/).
  Take full advantage of Facebook's support for complex data and activity by
  following the [Open Graph
  tutorial](https://developers.facebook.com/docs/opengraph/tutorial/).
  
  ```html
  <meta property="og:title" content="">
  <meta property="og:description" content="">
  <meta property="og:image" content="">
  ```
  
  ### Twitter Cards
  
  Twitter provides a snippet specification that serves a similar purpose to Open
  Graph. In fact, Twitter will use Open Graph when Cards is not available. Note
  that, as of this writing, Twitter requires that app developers activate Cards
  on a per-domain basis. You can read more about the various snippet formats
  and application process in the [official Twitter Cards
  documentation](https://dev.twitter.com/docs/cards).
  
  ```html
  <meta name="twitter:card" content="summary">
  <meta name="twitter:site" content="@site_account">
  <meta name="twitter:creator" content="@individual_account">
  <meta name="twitter:url" content="http://www.example.com/path/to/page.html">
  <meta name="twitter:title" content="">
  <meta name="twitter:description" content="">
  <meta name="twitter:image" content="http://www.example.com/path/to/image.jpg">
  ```
  
  
  ## URLs
  
  ### Canonical URL
  
  Signal to search engines and others "Use this URL for this page!" Useful when
  parameters after a `#` or `?` is used to control the display state of a page.
  `http://www.example.com/cart.html?shopping-cart-open=true` can be indexed as
  the cleaner, more accurate `http://www.example.com/cart.html`.
  
  ```html
  <link rel="canonical" href="">
  ```
  
  ### Official shortlink
  
  Signal to the world "This is the shortened URL to use this page!" Poorly
  supported at this time. Learn more by reading the [article about shortlinks on
  the Microformats wiki](http://microformats.org/wiki/rel-shortlink).
  
  ```html
  <link rel="shortlink" href="h5bp.com">
  ```
  
  ### Separate mobile URLs
  
  If you use separate URLs for desktop and mobile users, you should consider
  helping search engine algorithms better understand the configuration on your
  web site.
  
  This can be done by adding the following annotations in your HTML pages:
  
  * on the desktop page, add the `link rel="alternate"` tag pointing to the
    corresponding mobile URL, e.g.:
  
    `<link rel="alternate" media="only screen and (max-width: 640px)" href="http://m.example.com/page.html" >`
  
  * on the mobile page, add the `link rel="canonical"` tag pointing to the
    corresponding desktop URL, e.g.:
  
    `<link rel="canonical" href="http://www.example.com/page.html">`
  
  For more information please see:
  
  * https://developers.google.com/webmasters/smartphone-sites/details#separateurls
  * https://developers.google.com/webmasters/smartphone-sites/feature-phones
  
  
  ## Web Apps
  
  There are a couple of meta tags that provide information about a web app when
  added to the Home Screen on iOS:
  
  * Adding `apple-mobile-web-app-capable` will make your web app chrome-less and
  provide the default iOS app view. You can control the color scheme of the
  default view by adding `apple-mobile-web-app-status-bar-style`.
  
    ```html
  <meta name="apple-mobile-web-app-capable" content="yes">
  <meta name="apple-mobile-web-app-status-bar-style" content="black">
  ```
  
  * You can use `apple-mobile-web-app-title` to add a specific sites name for the
  Home Screen icon. This works since iOS 6.
  
    ```html
  <meta name="apple-mobile-web-app-title" content="">
  ```
  
  For further information please read the [official
  documentation](https://developer.apple.com/library/safari/#documentation/AppleApplications/Reference/SafariHTMLRef/Articles/MetaTags.html)
  on Apple's site.
  
  
  ### Apple Touch Icons
  
  The Apple touch icons can be seen as the favicons of iOS devices.
  
  The main sizes of the Apple touch icons are:
  
  * `57×57px` – iPhone with @1x display and iPod Touch
  * `72×72px` – iPad and iPad mini with @1x display running iOS ≤ 6
  * `76×76px` – iPad and iPad mini with @1x display running iOS ≥ 7
  * `114×114px` – iPhone with @2x display running iOS ≤ 6
  * `120×120px` – iPhone with @2x and @3x display running iOS ≥ 7
  * `144×144px` – iPad and iPad mini with @2x display running iOS ≤ 6
  * `152×152px` – iPad and iPad mini with @2x display running iOS 7
  * `180×180px` – iPad and iPad mini with @2x display running iOS 8
  
  Displays meaning:
  
  * @1x - non-Retina
  * @2x - Retina
  * @3x - Retina HD
  
  More information about the displays of iOS devices can be found
  [here](https://en.wikipedia.org/wiki/List_of_iOS_devices#Display).
  
  In most cases, one `180×180px` touch icon named `apple-touch-icon.png`
  and including:
  
  ```html
  <link rel="apple-touch-icon" href="apple-touch-icon.png">
  ```
  
  in the `<head>` of the page is enough. If you use art-direction and/or
  want to have different content for each device, you can add more touch
  icons as written above.
  
  For a more comprehensive overview, please refer to Mathias' [article on Touch
  Icons](https://mathiasbynens.be/notes/touch-icons).
  
  
  ### Apple Touch Startup Image
  
  Apart from that it is possible to add start-up screens for web apps on iOS. This
  basically works by defining `apple-touch-startup-image` with an according link
  to the image. Since iOS devices have different screen resolutions it is
  necessary to add media queries to detect which image to load. Here is an
  example for a retina iPhone:
  
  ```html
  <link rel="apple-touch-startup-image" media="(max-device-width: 480px) and (-webkit-min-device-pixel-ratio: 2)" href="img/startup-retina.png">
  ```
  
  However, it is possible to detect which start-up image to use with JavaScript.
  The Mobile Boilerplate provides a useful function for this. Please see
  [helpers.js](https://github.com/h5bp/mobile-boilerplate/blob/v4.1.0/js/helper.js#L336-L383)
  for the implementation.
  
  
  ### Chrome Mobile web apps
  
  Chrome Mobile has a specific meta tag for making apps [installable to the
  homescreen](https://developer.chrome.com/multidevice/android/installtohomescreen)
  which tries to be a more generic replacement to Apple's proprietary meta tag:
  
  ```html
  <meta name="mobile-web-app-capable" content="yes">
  ```
  
  Same applies to the touch icons:
  
  ```html
  <link rel="icon" sizes="192x192" href="highres-icon.png">
  ```
  
  ### Theme Color
  
  You can add the [`theme-color` meta extension](https://github.com/whatwg/meta-theme-color)
  in the `<head>` of your pages to suggest the color that browsers and
  OSes should use if they customize the display of individual pages in
  their UIs with varying colors.
  
  ```html
  <meta name="theme-color" content="#ff69b4">
  ```
  
  The `content` attribute extension can take any valid CSS color.
  
  Currently, the `theme-color` meta extension is supported by [Chrome 39+
  for Android Lollipop](http://updates.html5rocks.com/2014/11/Support-for-theme-color-in-Chrome-39-for-Android)
  and [Firefox OS 2.1+](https://twitter.com/ahmednefzaoui/status/492344698493997057).